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Topic Review
High-Performance Laser Scribing of Thin Film Solar Cells
The development of thin-film photovoltaics has emerged as a promising solution to the global energy crisis within the field of solar cell technology. However, transitioning from laboratory scale to large-area solar cells requires precise and high-quality scribes to achieve the required voltage and reduce ohmic losses. Laser scribing has shown great potential in preserving efficiency by minimizing the drop in geometrical fill factor, resistive losses, and shunt formation. However, due to the laser induced photothermal effects, various defects can initiate and impact the quality of scribed grooves and weaken the module’s efficiency. In this regard, much research has been conducted to analyze the geometrical fill factor, surface integrity, and electrical performance of the laser scribes to reach higher power conversion efficiencies.
  • 3.1K
  • 26 May 2023
Topic Review
2017 Catalan Independence Referendum
The Catalan independence referendum of 2017, also known by the numeronym 1-O (for "1 October") in Spanish media, was an independence referendum held on 1 October 2017 in the Spanish autonomous community of Catalonia, passed by the Parliament of Catalonia as the Law on the Referendum on Self-determination of Catalonia and called by the Generalitat de Catalunya. It was declared unconstitutional on 7 September 2017 and suspended by the Constitutional Court of Spain after a request from the Spanish government, who declared it a breach of the Spanish Constitution. Additionally, in early September the High Court of Justice of Catalonia had issued orders to the police to try to prevent it, including the detention of various persons responsible for its preparation. Due to alleged irregularities during the voting process as well as to the use of force by the National Police Corps and Civil Guard, international observers invited by the Generalitat declared that the referendum failed to meet the minimum international standards for elections. The referendum was approved by the Catalan parliament in a session in which only nationalist parliamentarians participated on 6 September 2017 along with the Law of juridical transition and foundation of the Republic of Catalonia the following day 7 September, which stated that independence would be binding with a simple majority, without requiring a minimum turnout. After being suspended, the law was finally declared void on 17 October, being also unconstitutional according to the Statute of Autonomy of Catalonia which requires a two-thirds majority, 90 seats, in the Catalan parliament for any change to Catalonia's status. The referendum question, which voters answered with "Yes" or "No", was "Do you want Catalonia to become an independent state in the form of a republic?". The "Yes" side won, with 2,044,038 (92.01%) voting for independence and 177,547 (7.99%) voting against, on a turnout of 43.03%. The Catalan government estimated that up to 770,000 votes were not cast due to polling stations being closed off during the police crackdown, although the "universal census" system introduced earlier in the day allowed electors to vote at any given polling station. Catalan government officials have argued that the turnout would have been higher were it not for Spanish and Catalan police suppression of the vote. On the other hand, most voters who did not support Catalan independence did not turn out, as the constitutional political parties asked citizens not to participate in what they considered an illegal referendum. Additionally, numerous cases of voters casting their votes several times or with lack of identification were reported, and the counting process and the revision of the census were not performed with quality standards ensuring impartiality. In the days leading to the referendum, the High Court of Justice of Catalonia ordered police forces to impede the use of public premises for the imminent voting. However, on the day of the referendum, the inaction of part of the autonomous police force of Catalonia, the Mossos d'Esquadra, allowed many polling stations to open. The National Police Corps and the Guardia Civil intervened and raided several polling stations after they opened. 893 civilians and 111 agents of the National Police and the Guardia Civil were reported to have been injured. According to various sources these previously reported figures may have been exaggerated. According to the judge from Barcelona who is currently investigating the accusations of police violence, there were 218 persons injured on that day in the city of Barcelona alone, 20 of whom were agents. According to the official final report by the Catalan Health Service (CatSalut) of the Generalitat 1066 civilians, 11 agents of the National Police and the Guardia Civil and 1 agent of the regional police, the Mossos d'Esquadra, were injured. The United Nations High Commissioner for Human Rights, Zeid Ra'ad Al Hussein, urged the Spanish government to prove all acts of violence that took place to prevent the referendum. The police action also received criticism from Amnesty International and Human Rights Watch which defined it as an "excessive and unnecessary use of force". Spanish Supreme Court judge Pablo Llarena stated Puigdemont ignored the repeated warnings he received about the escalation of violence if the referendum was held. Mossos d'Esquadra are being investigated for disobedience, for allegedly not having complied with the orders of the High Court of Justice of Catalonia. Including Josep Lluís Trapero Álvarez, the Mossos d'Esquadra major, who is being investigated for sedition by the Spanish National Court. Mossos d'Esquadra deny those accusations and allege they obeyed the orders but applied the principle of proportionality, which is required by Spanish law in all police operations.
  • 3.1K
  • 07 Nov 2022
Topic Review
Bisphenols
Bisphenols (BPs), and especially bisphenol A (BPA), are known endocrine disruptors (EDCs), capable of interfering with estrogen and androgen activities, as well as being suspected of other health outcomes.
  • 3.1K
  • 28 Oct 2020
Topic Review
Blue Gene
Blue Gene is an IBM project aimed at designing supercomputers that can reach operating speeds in the PFLOPS (petaFLOPS) range, with low power consumption. The project created three generations of supercomputers, Blue Gene/L, Blue Gene/P, and Blue Gene/Q. Blue Gene systems have often led the TOP500 and Green500 rankings of the most powerful and most power efficient supercomputers, respectively. Blue Gene systems have also consistently scored top positions in the Graph500 list. The project was awarded the 2009 National Medal of Technology and Innovation. As of 2015, IBM seems to have ended the development of the Blue Gene family though no public announcement has been made. IBM's continuing efforts of the supercomputer scene seems to be concentrated around OpenPower, using accelerators such as FPGAs and GPUs to battle the end of Moore's law.
  • 3.1K
  • 29 Sep 2022
Biography
Julius Edgar Lilienfeld
Julius Edgar Lilienfeld (April 18, 1882 – August 28, 1963) was a Jewish Austro-Hungarian-born German-American physicist and electronic engineer, credited with the first patents on the field-effect transistor (FET) (1925) and electrolytic capacitor (1931). Because of his failure to publish articles in learned journals and because high-purity semiconductor materials were not available yet, his
  • 3.1K
  • 10 Nov 2022
Topic Review
UAVs to CBRN Threats monitoring
Unmanned aerial vehicles (UAVs) play an increasingly important role in various areas of life, including in terms of protection and security. The possibilities of using the devices were analyzed in terms of weather conditions, construction, and used materials in CBRN (chemical, biological, radiological, nuclear) threat situations. It was found that, thanks to the use of appropriate sensors, cameras, and software of UAVs integrated with a given system, it is possible to obtain information on air quality at a given moment, which is very important for the safety of people and the environment. However, several elements, including the possibility of use in acidification conditions, requires refinement to changing crisis conditions.
  • 3.1K
  • 28 Dec 2020
Topic Review
Energy Harvesting from Fluid Flow Using Piezoelectric Materials
The use of piezoelectric-energy harvesting has grown in popularity during the previous two decades. Several implantable energy-harvesting technologies are being developed by scientists to power portable gadgets and medical equipment. Thanks to new technologies, researchers have been able to fabricate highly flexible piezoelectric devices and electronics, paving the way for the development of biocompatible and long-lasting harvesters. 
  • 3.1K
  • 16 Dec 2022
Topic Review
Drilling Fluids for Extended-Reach Wells
In the planning phase of extended-reach well (ERW), special attention should be paid to the choice of drilling fluid. Selected drilling fluids for extended-reach wells should satisfy the same basic functions that are common to all drilling fluids, and they have to provide excellent reservoir protection. When drilling extended-reach wells, the following critical factors should be considered: hole cleaning, torque and drag, borehole stability, equivalent circulating density (ECD) and lost circulation. So far, oil-based mud (OBM) and water-based mud (WBM) have also been used in practice, but the emphasis is on the application of environmentally friendly additives.
  • 3.1K
  • 06 Apr 2023
Topic Review
Fe-Based Magnetic Amorphous Alloys
Amorphous alloys for soft magnetic applications are often fabricated by rapid solidification of the melt. They are generally prepared with the nearly 20% addition of metalloids (Si, B, Al, C and P) for Fe-based and Co-based alloys. Si and B are important metalloids for glass formation and the amorphous structure stabilisation. Typical chemical compositions are such that the combined compositions of Fe, Co, Ni elements are 70–85 atomic (at.)% and those of Si and B are 15–30 at.% in total. However, magnetic glassy alloys have a wide variety of compositions. This allows for a large range of soft magnetic properties to be achieved, which depend upon the demands of the application.
  • 3.1K
  • 28 Apr 2021
Topic Review
Dendrocalamus asper and Related Bamboos
Bamboos represent an emerging forest resource of economic significance and provide an avenue for sustainable development of forest resources. The development of the commercial bamboo industry is founded upon efficient molecular and technical approaches for the selection and rapid multiplication of elite germplasm for its subsequent propagation via commercial agro-forestry business enterprises. 
  • 3.1K
  • 08 Nov 2021
Topic Review
African American Studies
African American studies (alternately Black studies, or Africana studies, among other terms) is an interdisciplinary academic field that is primarily devoted to the study of the history, culture, and politics of black people from the United States . African American studies are a sub-field of African diaspora studies and Africana studies, the study of the people of African origin worldwide. The field has been defined in different ways, but taken broadly, it not only studies African slave descendants but also any community of the African diaspora linked to the Americas. The field includes scholars of African American (as well as Caribbean, African, and Afro-European) literature, history, politics, and religion as well as those from disciplines such as sociology, anthropology, cultural studies, psychology, education, and many other disciplines within the humanities and social sciences. And, increasingly, African American Studies departments are hiring and partnering with STEM scholars. Intensive academic efforts to reconstruct African American history began in the late 19th century (W. E. B. Du Bois, The Suppression of the African Slave-trade to the United States of America, 1896). Among the pioneers in the first half of the 20th century were Carter G. Woodson, Herbert Aptheker, Melville Herskovits, and Lorenzo Dow Turner. Programs and departments of African American Studies were first created in the 1960s and 1970s as a result of inter-ethnic student and faculty activism at many universities, sparked by a five-month strike for black studies at San Francisco State. In February 1968, San Francisco State hired sociologist Nathan Hare to coordinate the first black studies program and write a proposal for the first Department of Black Studies; the department was created in September 1968 and gained official status at the end of the five-months strike in the spring of 1969. The creation of programs and departments in black studies was a common demand of protests and sit-ins by minority students and their allies, who felt that their cultures and interests were underserved by the traditional academic structures. Black studies is a systematic way of studying black people in the world – such as their history, culture, sociology, policies, experience, issues and religion. It is a study of the black experience and the effect of society on them and their effect within society. This study aims to, among other things, help eradicate many racial stereotypes. Black studies implements history, family structure, social and economic pressures, stereotypes, and gender relationships.
  • 3.1K
  • 04 Nov 2022
Topic Review
Solar Radiation Management
Solar radiation management (SRM) proposals are a type of climate engineering which would seek to reflect sunlight and thus reduce global warming. Proposed methods include increasing the planetary albedo, for example using stratospheric sulfate aerosols. Restorative methods have been proposed regarding the protection of natural heat reflectors like sea ice, snow and glaciers with engineering projects. Their principal advantages as an approach to climate engineering is the speed with which they can be deployed and become fully active, their potential low financial cost, and the reversibility of their direct climatic effects. Solar radiation management projects could serve as a temporary response while levels of greenhouse gases can be brought under control by mitigation and greenhouse gas removal techniques. They would not reduce greenhouse gas concentrations in the atmosphere, and thus do not address problems such as ocean acidification caused by excess carbon dioxide (CO2).
  • 3.1K
  • 24 Nov 2022
Topic Review
Ocotillol-Type Triterpenoids
Ginseng is one of the most widely consumed herbs in the world and plays an important role in counteracting fatigue and alleviating stress. The main active substances of ginseng are its ginsenosides. Ocotillol-type triterpenoid is a remarkably effective ginsenoside from Vietnamese ginseng that has received attention because of its potential antibacterial, anticancer and anti-inflammatory properties, among others. The semisynthesis, modification and biological activities of ocotillol-type compounds have been extensively studied in recent years.
  • 3.1K
  • 09 Dec 2020
Topic Review
Nanomaterials Combined with Bacteriocins
Bacteriocins are antimicrobial peptides or proteinaceous materials produced by bacteria against pathogens. These molecules have high efficiency and specificity and are equipped with many properties useful in food-related applications, such as food preservatives and additives, as well as biomedical applications, such as serving as alternatives to current antibacterial, antiviral, anti-cancer, and antibiofilm agents. Despite their advantages as alternative therapeutics over existing strategies, several limitations of bacteriocins, such as the high cost of isolation and purification, narrow spectrum of activity, low stability and solubility, and easy enzymatic degradation, need to be improved. Nanomaterials are promising agents in many biological applications. They are widely used in the conjugation or decoration of bacteriocins to augment the activity of bacterioc-ins or reduce problems related to their use in biomedical applications. Therefore, bacteriocins combined with nanomaterials have emerged as promising molecules that can be used in various biomedical applications.
  • 3.1K
  • 11 Oct 2021
Topic Review
Aqueous Soluble Drug
The low water solubility of pharmacoactive molecules limits their pharmacological potential, but the solubility parameter cannot compromise, and so different approaches are employed to enhance their bioavailability. Pharmaceutically active molecules with low solubility convey a higher risk of failure for drug innovation and development. Pharmacokinetics, pharmacodynamics, and several other parameters, such as drug distribution, protein binding and absorption, are majorly affected by their solubility.
  • 3.1K
  • 20 Sep 2022
Topic Review
Metal Matrix Composite
Composites are generally categorized into three main categories based on the matrix substance. They are called metal matrix composite (MMC), polymer matrix composite (PMC), and ceramic matrix composite (CMC), respectively. MMC gives more elevated ductile properties than CMCs and better environmental stability than PMCs. Additionally, MMCs offer good thermal conductivity (from 220 to 580 W·m−1·K−1), wear resistance (0.01025), wear rate (g·m−1), erosion, and shear strength.
  • 3.1K
  • 06 Sep 2021
Topic Review
Balloon (Aeronautics)
In aeronautics, a balloon is an unpowered aerostat, which remains aloft or floats due to its buoyancy. A balloon may be free, moving with the wind, or tethered to a fixed point. It is distinct from an airship, which is a powered aerostat that can propel itself through the air in a controlled manner. Many balloons have a basket, gondola, or capsule suspended beneath the main envelope for carrying people or equipment (including cameras and telescopes, and flight-control mechanisms).
  • 3.1K
  • 27 Oct 2022
Topic Review
Virtual Reality and Metacognition for Learning Disabilities
Learning disabilities are defined as a set of neurodevelopmental disorders of biological basis that induce cognitive abnormalities as well as symptoms related to emotional and behavioral disorders. Metacognition is defined by Drigas and Mitsea as the “set of regulatory meta-abilities and meta-skills that are consciously applied aiming at the smooth operation of the cognitive & psychophysiological mechanism as a means of achieving functional capability, self-efficacy, independent living & life satisfaction. Virtual reality (VR) is commonly regarded as a technology that induces virtual immersion in a digital world via the use of a computerized graphic simulation that allows users to immerse themselves in an interactive three-dimensional world brimming with various sensory and emotional experiences.
  • 3.1K
  • 21 Oct 2022
Topic Review
Structure and Formation of Chitin
Due to the properties such as biodegradability, biocompatibility, non-toxicity, physiological inertness, and gel-forming properties, chitin has been found to have countless applications in different industries, e.g., food, cosmetic, pharmaceutical, manufacturing of synthetic materials, agriculture, and even electronics for the production of biosensors. It's important to understand the structure and formation of chitin.
  • 3.1K
  • 22 Nov 2022
Topic Review
Filamentous Bacteriophage Delivery System
Bacteriophages are a powerful platform with outstanding potential in the biomedical and chemical engineering field that have been exploited for diverse applications including theranostics, batteries, drug delivery, and vaccine development. Filamentous bacteriophages are single-strand DNA virions belonging to the Inoviridae family, a sub-group of non-lytic, rod-like shaped Escherichia coli viruses with a repeated and ordered capsid structure, and that includes phages f1, fd, and M13. Fd filamentous bacteriophage is a bio nano-fiber with a modifiable surface that is a promising vehicle for antigen expression.
  • 3.1K
  • 30 Oct 2020
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